v-m: Scrape metrics from Authelia

Authelia exposes Prometheus metrics from a different server socket,
which is not enabled by default.

authelia/authelia.yaml

@@ -66,6 +66,13 @@ spec:
           value: /run/authelia/secrets/oidc.hmac_secret
         - name: AUTHELIA_IDENTITY_PROVIDERS_OIDC_ISSUER_PRIVATE_KEY_FILE
           value: /run/authelia/secrets/oidc.issuer_private_key
+        ports:
+        - containerPort: 9091
+          name: http
+          protocol: TCP
+        - containerPort: 9959
+          name: metrics
+          protocol: TCP
         startupProbe:
           httpGet:
             port: 9091

authelia/configuration.yml

@@ -157,3 +157,7 @@ storage:
     username: authelia.authelia
     tls:
       skip_verify: false
+
+telemetry:
+  metrics:
+    enabled: true